Dental lathe-file.



W. P. RICHARDS. DENTAL LATHE FILE. APPLICATION FILED MAR.18, 1912.

1, 1 05,456. Patented July 28, 1914.

Fig.5.

Fig.8.

Illb NORRIS PETER: \ll PHOTU-LITIKL. WASHINGTON. Dv C TE ST OFFICE.

WALTER F. RICHARDS, 0F QUINCY, ILLINOIS.

DENTAL LATHE-FILE.

Specification of Letters Patent.

Patented July 28, 1921.4.

Application filed March 18, 1912. Serial No. 684,649.

To all whom it may concern Be it known that I, WVAL'rna F. RICHARDS, a citizen of the United States, resident of Quincy, in the county of Adams and State of Illinois, have made a certain new and useful Invention in Dental Lathe-Files; and I declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it appertains to make and use the invention, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

Figure 1 is a side view of the invention as applied. Fig. 2 is a section on the line 2-2, Fig. 1. Fig. 3 is a top plan view of the file. Fig. 4: is a bottom plan view of the file. Fig. 5 is a section on the line 5-5, Fig. 1. Fig. 6 is a top plan view of another form of the invention. Fig. 7 is a bottom plan view of the same. Fig. 8 is a section on the line 88, Fig. 6.

The invention has relation to dental lathe files, having for its object to provide improved means for surfacing and festooning the vulcanite between and about the necks of the teeth in artificial dentures, and it consists in the novel construction and combinations of parts, as hereinafter set forth.

In the accompanying drawings, illustrating the invention, the numeral 1 designates the short flat blade of the file, of general triangular flat or V-form, having a flat smooth top 2 and a fiat bottom 3, converging oppositely beveled straight lateral edges 4: terminating in an acute angle point and a rear end tang extension 5.

The bottom surface of the file is file cut straight across from side to side at right angles to the longitudinal axis of the file in a parallel manner, as shOWn at 6, 6, to provide a series of transverse serrations extending from the heel to the point of the blade.

The tang has a beveled edge portion 7 at one side and at the opposite side is provided with an extension 8 the outer edge 9 of which is concave, and beveled at 10. This tang is designed to fit within a beveled-edge groove 11 of the slide bar of the lathe, a rounded or cone-end set screw 12 having engagement with the concave outer edge of said extension, to force the opposite beveled edge portion of the tang against the similarly formed edge wall of the slide groove and hold the file securely against displacement or being shaken loose at the high speed at which it is run in practice.

One form of the invention is shown in Figs. 1-5 of the drawings, whecrin the lat eral edges of the file are oppositely beveled in a convex manner at 13, said edges having each a series of oblique file teeth 14, terminating short of the wider face of the file as indicated at 4, so that they are thereby rendered safe or non-cutting.

A second form of the invention is shown in Figs. 6, 7 and 8 of the drawings, wherein the lateral edges of the file are oppositely beveled, at 16, the bottom surface of the file being flat from side to side, and the oblique file teeth being omitted. In this form of the invention, the transverse teeth 6, may be sharpened when worn by regrinding the bevel of the edges.

Both forms of the file are capable of being stamped from sheet metal of the same thickness throughout.

The file is of delicate, thin character and is preferably of a length about equal to twice its width, in order that it may be strong and not bend too easily. The inclination given the lateral edges of the file in this way will also provide for proper cutting action of said edges, which run close up to the necks of the artificial teeth. The parallel teeth are designed to act in the manner of a succession of sharp planing edges upon the vulcanite, and are required to be at right angles to the longitudinal axis of the file for this purpose.

The straight lateral edges converge at an angle and are reduced by the bevel thereof to comparative thinness, for working in narrow places of the vulcanite. The oppositely beveled edges form, with the opposite face of the file, a three-sided point, useful in working in corners.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is A dental lathe file, having, a thin fiat V form blade provided With straight oppositely serrations extending to the extremity of said beveled lateral edges converging at an angle, point. 10 a fiat Working face having a series of trans In testimony whereof I aflix my signature, verse serrations,ia plane back surface, and in presence oftWo Witnesses.

5 a three-sided point formed by the beveled WALTER F. RICHARDS.

lateral edges and the opposite face of the lVitnesses: file, said beveled lateral edges-being reduced LYMAN MQCARL, to comparative thinness and said transverse v J HN T. INGHRAM.

@Qpiet of {this patent may be obtained for flve iieiits each, by addressing the Commissioner, Patents. Washington, a. G. 

